What is the problem when your new tile on a cement floor sounds hollow when you tap on it?

Question

What is the problem when your new tile on a cement floor sounds hollow when you tap on it?

Answer 1

The problem would be that there is not enough mastic/adhesive behind it and it was not set right. This is a bigger problem and you may want to take the tile up and spread some more mortar/adhesive on the back of it to give it a better grip.

Answer 2

not enough adhesive behind the tile, you would get away with it on a wall, but on a floor, the tile will break sooner or later as the adhesive should be uniform all over the floor, get whoever did the job to fix it, and if yoou did it yourself, you will probably ned to break the tile out and replace it with a new one, and use a serrsted trowel to put the new adhesive down and bed the new tile into place, and while you're at it, tap on the other tiles too and if they're hollow too, you may have to re-do the whole job again,